High frequency signaling apparatus



Jan. 8, 1935.. L. A. GEBHARb 8 ,8

HIGH FREQUENCY SIGNALING APPARATUS Fi led Jan. 27, 1953 s Sheets-Sheet 1 INVENTOR.

M a M ATTORNEY g Jan. 8, 1935. A. GEBHARD HIGH FREQUENCY SIGNALING- APPARATUS Filed Jan. 27, 1953 3 SheetsSheet2 ATTORNEY IN V EN TOR Q .Qik w Jan. 8, 1935. A, GEBHARD 1,986,804

HIGH FREQUENCY SIGNALING APPARATUS Filed Jan. 27, 1955 s Sheets-Sheetfi Z ESE-3'- A TTORNEY Patented Jan.8 ,"1935 r v 1,986,804 b i .t 1 men FnEQUENcr SIGNALING APPAn 'rUs 1 Louis A. Gebhard,'Was hi1 1gton, p. hpplicationJanuary 27, 1933,? seriai 1Q'c 6 5 3,885 y 20 Qlaims. (01.250 47) c (Granted :u nder thetact of TMarchy3,38:51am

amended April 30,1928; 370G. 757) Myinvention relates broadly to signaling systems and more particularly' to a high frequency sembly.

' frequency circuitsm transmitting system. n "One of the objects of my invention isto provide aconstruction of high frequency signal transmitting apparatus which is efiicientin its construction and simple in its manufacture and as- Another object of my invention is to provide" a construction of high frequency signal transmit ting apparatus wherein theleng'th ofthe leads interconnecting the inductance system with the electron tube'elernents employed i-nthetrans mission circuits are 'reduced'to an absolute minimum for improving the efiiciency oi thetrans mitten v v it :Still another object of my invention is to provide a construction of high frequency signal transmission apparatus in which electron tubes of the high power'type are mounted concentrically with theaxes of the tuning inductance units and adjustmento'f inductance obtained by contactors which move in paths immediately-below the high power tubes in positions requiring-mim mum length of leads-between parts ofthe high further object of my invention istoprovide a construction of high frequency signal transmitting apparatus which fluid cooled electron tubes are employed'and'the fluid cooledind-udtances associated with the fluid cooled tubes in positions adjacent the fiuidcooled tubes and. a fluid path of a minimumlength provided through the fiuidcooled tubes and the inductancesfor insuring operation of the apparatus atmaximum efiiciency l l A still further object of my invention is to protern including electron'tubes and high frequency inductance units soassociated asto provide maxe imum inductance with minimurn. external field I in and minimum coupling to'other parts of: the

Another objectgof my invention is to provide an arrangement of cooling fluid system for balanced high frequency electron tube'circuits in which inductance lunits are concentrically dis:

posed along the axesvofithe electron tubes and cooling fluid so distributed as to insuremaximum cooling operation with minimum radio frequency losses. i i Other and further side in the compact assembly. of high frequency 1 i signaling apparatus for the efficient transmission .of signals over a predetermined range of firequencies as will beset ionthjmore iully in'the objects of ,my invention re-' system employed inthe transmitter of my invention and showing the relation of the inductance v s system to the highpowe r tubes employed in the transmitting circuit; Fig.2 is a bottom plan. view of the inductance system employed-inthe'transmission apparatus of my invention; Fig; 3 is a transverse sectional View taken throughrthe in- 10 ductance system on line 3- 3 10 f Fig. ei liig. Lis anfelevational view of the inductance 'systeni illustrating the association thereof with the high is power tubes and showingparts of the. inductance systemin cross section forillustrating theadjust- 15 ing means by which -the ffrequency of operation of i the apparatus is predetermined; Figi 5 is a wiring diagram illustrating the? electrical connection of the apparatusin thesystem of my in- 6 is a schematic viewfshowing the path of thefluidcoolingmedium through the ind ctance units andraround {the anodes of the thigh' power tubes; in the {system of my invention." y In a radio transmitter-having' a;high1 power utputyitis important that the e fficiencyofthe circuitbeas' high as possible. [Tel this end it is necessary that thefloutput circuit of the high power amplifier bearranged tohave the proper L/C ratio. Itisvery "simple, t'o'do this at low 39 frequencies; At'high frequencies, however; the

capacities inthe circuitprovide capacity react the proper L/ C. ratio and still cover a wide ire-'- qu cfy ha T eilse ,ofi n u v t i ra her ha cap i ative vtun n jpem or r tiqn of the transmitter over a ,wide frequencyband. The inductance; however, should be'fvaried by'cutting it out of the circuit. in a. continuously variable arrangementso asto give continuous variation of frequency, To go-up as high as possible in frequency, the system must be so arranged that a minimum of inductance remains infthe circuit. Theoutput circuit of a high power amplifier inyolves a still furtherproblem in design. This is the introduction opat cooling 'fiuid to maintain the anode of the high powertubeand the inductance system at the proper temperature.- The s'ystemshown in the accompanying figures meet's these requirements. l

In order to reduce' the tance, in the circuit at minimum position, the

liquid-cooling jackets 1 and 1' containing the itsouter surface a spiral square shaped thre'ad'l2'.

Cylindrical member 13 holds brush 8 about tube 9.

The upper end of cylindrical member '13 is pro vided with a multiplicity of slots for increasing the resiliency of the sleevelike portion of member 13 for providing a good connection with tube 9.

A combination screw and pin 14 screws into member 13 and passes through a longitudinal slot 50 in tube 9 into thesquare thread in the outer surface of 12. The. rotating of tube 9 causes the .rotation of brush 8 as well as imparting sliding movement longitudinally of the inductance to conform to the pitch of the coil. Gear 10 is attached to'tube 9 and is driven by worm 15 through insulating members 16 and 17 from 'a crank 18 mounted on the front panel 19 of the radio transmitter. A counter mechanism 20 is provided to indicate the adjustment. ,Inside of tube llis located another tube 21 which passes into the lower end of the shaft and extends upward into the jacket 1. The lower ends of coil 3 are-connectedv through tubes 22 and 23 respectively to the space between tubes 21 and 11 and to the lower end of tube 21. l

The two halves of the system are symmetrical and connected together at point 24. An inlet 25 and an outlet 26 are provided for the cooling fluid.

An electrical connection is also made at this point so that the positive anode potential may be fed; in from' the power source as shown in Fig.5. It should be noted thatthe turns of the two coils are wound in the same direction so as to "provide maximum inductance with. minimum external field and minimum coupling to other parts-of the system.

Fig. 6 shows-the fiuid cooling circuits of .the system ofmy invention. The cooling fluid enters the system at 27,-passes up through the insu-' lating-hose coil-28 into the inductance, system at 25 whereitdivides so as to pass into coils 3 and 3'. Itgentersthese coils at the top, (Fig. 4) passes through the conductorthroughtubes 23 and 21 into the fluid jacket 1. In the jacket the cooling fluid passes over the surface of the anode to the-top, returningthrough discharge outlet 29 downtothespace between tubes 21 and" 11 through tube 22 up back through the conductor to outlet 26 through the insulating hose coil, 30 discharging at 31. 1

Fig. 5 shows the electrical connections of the system. With the structural arrangement shown, it will be'se en that the shaft of the coil is directly connected through the jacket 1 to the anode of the electron tube.; This connection is a very short one. When the brushes 8 are at the toplof the coil, the only inductance in the circuit is throughlthe brushes to connection 24 which is extremely short. It will be seen thatthe' unused portions of the coil, which are the lower portions;

are short circuited. Sincethe system contains 0.

two short ,circuited portions in the two halves of the system, the possibility of setting up resonant currentsin these shortcircuited portions is a Their natural period is at a very high frequency beyond, the frequency range of the: transmitter. 'If desired, condenser 32 may be connected in parallel with the inter-element and distributed capacities of the circuit to augment the frequency range of the transmitter. The electron tubes 2 and 2 are shown in this figure as four element tubes with a screen grid connection. I may employ three element tubes in the usual push pull balance system. Fig. 5 shows an amplifier circuit where the input is at 33 and the output at 34. The simultaneously controlled condensers 35 and 35' are provided for coupling adjustments.

The input inductance is provided with adjustable'taps represented at 33a and 33b movable over inductance 33 for including the required number of turns in the circuits leading to the cathodes 2b and 2'b is supplied from transformer 40. The plate potential is connected across terminals 41 across which the bypass condenser 42 connects. The plate circuit is completed as illustrated by the connection which leads to terminal24 through inductance units 3 and 3 to the anodes 2c and 2'0 as shown. The potential for energizing the screen grids 2d and Z'd is derived from sources which connect across terminals 43 and 44. Bypass condensers 45 and 46 are arranged across the potential sources 43 and 44 as shown. Suitable balancing condensers 4'7 are connected in'the cathode circuit as shown. The extension of the frequency over which the transmitter maybe adjusted is accomplished by the connection of condenser 32 through contacts 32a and 32b with the inductances 3 and 3. Intermediate adjustments of frequency may be eiTected by movement of brushes 8 along the turns of the inductances 3 and 3.

The 1 arrangement of the electrical paths through the inductance units and the fluid cooling paths through the inductance units is such that the fluid cooling paths are arranged in parallel through the inductance units while the electrical paths through the independent inductance units are in series between the individual anodes and the source of potential. The cooling fluid supplied through inlet 27 passes in the opposite direction from the connection at 25 through each of the inductances 3 and 3'. The circulating fluid after it passes through electron tube jackets 1 and 1 by passing through conductors 23 and 23 and upwardly through tubes 21 and'21' is returned from, electron tube jackets around the annular spaces intermediate tube 21 and tube 11; circulating through the twin, conductor constituting the other part of the duplex inductance units 3 and 3' to the outlet26 where it is discharged through hose coil 30 and discharge pipe 31. The distribution of cooling fluid through the inductance units is, in this way, eifected'in parallel arrangement while the electrical circuits through the inductance units are established inindependent seriespaths constituting theioutput circuits of the separate electron tubes. a

By reason of the inherent shortness of the leads in the transmitting apparatus of my invention and the compact arrangement of the inductance and electron tube units, a transmitter of'high eificiency is obtained. The parts of the apparatus are so-arranged as to be readily {What I claim as new and Letters Patent of the United States, is as follows:

required repairs. 1 While I have replaceable and accessible for the making of the purposes withoutthe payment of any royalty thereon or therefor. V

desire to secure by I 1". Radio transmission apparatus comprising a let and discharge connections, a twin conductor fluid cooled inductance wound on an axis concentric: the aXisof, saidsockeu and hold passages-extending from the lower ends of said conductor axially .througli'f said inductance and connectedwith said fluid inlet and discharge connections in said fiuidco'oledfielectron tube socket, and fluid inlet and discharge connections at the upper end of said twin conductor fluid cooledinductancej I )2; In a high frequency-signaltransmission'sys tem, a set of electron tubes each having an aiially extending electrode, inductance units individual to each of said electron tubes andhav} theiraxes disposed on the axes of said tubes, and fluid cooling means for theaxially extending electrode of each of said electron-tubes e2;-

tending through each of said inductance -13. High frequency signaling apparatuscomw ductor inductance, a rotatable sleeve concentriprising a fiuidcooled electron tube apparatus having fluid 1 inlet i and discharge connections,

as inductance unitdisposed on an axis coincident with the aicis of said electron tube struccure, means extending through said inductance 'u" and adjustable to select-the eliective numb of turns in said inductance unit, and means interconnecting said fluid cooled inductance with th inlet and discharge connections of said electrjonftube apparatus gfor effectively cooling both saidelectron tube apparatus and said inductance.

frame-"structure, an electron inlet and discharge connections depending from saidelectron tube jacket through said frame structure, a fluid cooled inductance concentrically disposed around said tubular inlet discharge connections and means operative within said fluid cooled inductancefor controlling the effec' tive number of turnsinsaid inductance.

5.High frequency signaling apparatus com- I prising frame structure, a fluid cooledelectron biibe jacket said fluid cooled jacket providing inlet and discharge paths for the circulation of cooling fluid toandfrom said electron tube jacket, affluid cooled'inductance concentrically mounted about said tubes, fluid inlet anddischarge connections between said fluid cooled inductancefand the lowe'r portions of said tubes, and means operative l within saidinductance for controlling the eil'ec tive number of turns thereof. l

I 6. High "frequency signaling apparatus cornprising a frame structure, a fluid cooled electron tube jacket supported by said frame structure,

supported by said frame structure, concentrically disposed tubes depending from for the circulation of cooling fluidto andifrom said jacket a. twinmconductor fluid cooled in: ductance: concentrically mounted around said tubes, connections: between the ,lower portions of saidtubes. and therilower ends of said twin-conductor inductance, ,andmeans surrounding said tubes and angularly ad'justable,-.for controlling the effective numberlof turns insaid fluid cooled inductance S i )7. High frequency signaling apparatus comprising a fram' structure, arfiuidcooled electron tube jacket supported by said frame structure, concentrically disposed tubes depending from the lower portion offisaid'jacket and providingpaths for the circulation of coolingfluid to and from said jacket, a twin rconductor fluid cooled in;- ductance concentrically mounted around said tubes, connectionsrbetween the lower portions of tube jacket supportedfby, said, frame structure,

concentrically disposed tubes depending from the lower portion of said jacket and providing paths for the circulationof'coolingfluid to and from said jacket, a twinc'onductor fluid cooled inductance concentrically lmounted, around said tubes, connections between thelower portions of tubes and thelower ends of said twin concally mounted on said tubes, a radially positioned arm carried by said sleeve and adapted'to, move in a spiral pathtalong said inductance for selecting the effective number of turns in said inductance, and means for admittingand discharging cooling fluid at the upper end of said twincom ductor fluid cooled inductance. i 1 9;,High frequency signaling apparatus comprising a frame structure, a .fiuidcooled electron tube jacket mounted on said frame struct-ure, a

pair of concentrically positioned. tubes depending from said jacket and providing paths for the circulation of cooling fluid through said jacket, a spiral thread formed on the exterior of one of said tubes, a rotatablesleeve concentrically disposed upon the said last mentioned tube, an arm carried by said sleeve and having'a member extending through said sleeve and-engaging the screw threads formed on said last mentioned tube; atwin conductor fluid cooled inductance concentrically mounted about said sleeve,. a sliding contactor carried by-said arm and engaging theturns of said fluid cooled inductance, fluid inlet and discharge connections with the'upper end of said twinconductor inductance, fluid inlet and discharge connections between the lower ends of said twin conductorinductance and the said tubes for providing a fluid circulating path through said inductance and through said fluid cooled jacket. H

' l0. Inaw'balancedamplifier circuity'a pairof fluidcodledfl electron tubes, fluid cooled jackets for each of said; electron tubes, twin conductor fluid cooled: inductance units individual to each of said electron tubes, means for simultaneously controlling the effective number of turns in said inductance units, fluid inlet and discharge connectionsfor said inductance units, said inducand circuits electrically connecting the respective inductance units in series in the output circuits of each of said electron tubes.

12. High frequency signaling apparatus comprising'a frame structure, a'pair of fluid cooled inductance units extending on axes parallel to each other, fluid cooled tube jackets disposed in alignment with the axes of said inductance units, fluid conducting members interconnecting said'jackets with said inductance units, means foremitting and discharging cooling fluid to said inductance units for circulation therethrough and through said jackets and means for simultaneously controlling the effective number of turns in each of said inductance units.

13. High frequency signaling apparatus comprising a frame structure, a pair of fluid cooled jackets'carried by said frame structure on vertically disposed axesiparallel to each other, inductance unitscarried by said frame structure immediately below said jackets and'on axes coincident with the axes of said jackets, and rotatable means extending through said inductance units for selecting the'eifective number of turns in said inductance units, said inductance units being constituted by hollow tubular conductors connected withsaid fluid cooled jackets and connected with fluid inlet and discharge terminals for effectively cooling said inductance units an said tube jackets. 1 14. High frequency signaling apparatus comprising a frame structure, fluid cooled electron tube jackets carried by said frame structure, fluid cooled inductance units mounted on said frame structure and disposed concentrically about the axes of said jackets, connections between said jackets and said fluid cooled inductance units for the circulation of cooling fluid therethrough, and means operative within each of said inductance units for .short-circuiting the ineffective turns of said inductance units while establishing a separate series circuit through the effective turns of said inductance units.

15. In a balanced amplifier system, a pair of fluid cooled electron tube jackets, fluid cooled electron tubes mounted in said jackets, separate fluid cooled inductance units concentrically mounted with respect to each of said jackets and independently connected in series. relation in the output circuits'of the respective electron tubes, means for simultaneously controlling the eifective number of turns in said fluid cooled in- I ductance units, a tuning reactance, and means for electrically connecting said tuning reactance in parallel with said inductance units for extending the frequency range thereof.

16. A balanced amplifier comprising a pair of fluid cooled electron tubes, a fluid cooling jacket individual to each of said electron tubes, twin conductor inductance units concentrically mounted with respect to each of said jackets, tubular conductors interconnecting said jackets with the respective twin conductor inductance units, means for supplying and discharging cooling fluid to said cooling jackets through said inductance units, and circuit connections for establishing a series electrical path between the respective inductance units and the output circuit of each of said electron tubes. I

17. Radio transmitting apparatus comprising a frame structure, a pair of fluid cooled electron tube jackets carried by said frame structure, inductance units each comprising a twin tubular conductor concentrically wound with respect to the axis of said jackets, connections between the lower ends of the twin conductors constituting said inductance units and said fluid coolingjackets, and connections between the upper ends of said twin conductor inductance units and fluid inlet and discharge terminals for effectively cooling both said inductance units and said jackets.

18. High frequency signaling apparatus comprising a frame structure, a pair of fluid cooled electron tube jackets carried by said frame structure, inductance units vertically mounted on said frame structure adjacent each of said electron tube jackets, said inductance units each comprising a twin tubular conductor having the elements thereof wound immediately adjacent each other, a fluid supply connection, a fluid discharge connection, a tubular conductor extending from said fluid supply connection to one conductor at the upper end of each of the said inductance units, a tubular conductor extending from said fluid discharge connection to the other conductor at the upper end of each of the said bular inductance units concentrically disposed with respect to each of said fluid cooled jackets, means for simultaneously varying the effective number of turns in said inductance units, fluid conveying conduits interconnecting said inductance units with said fluid cooled jackets, a fluid supply terminal, a fluid discharge terminal, and parallel electrical connections between said terminals and fluid distribution paths.

20. Radio apparatus comprising a frame structure, a fluid cooled electron tube jacket carried by-said frame structure, fluid inlet and discharge connections for said jacket, a pair of concentrically disposed conduits connected with said fluid inlet and discharge connections, a duplex conductor inductance unit, insulation means carried by said frame structure and supporting the 

